Method for the assembly of lead-acid batteries and associated apparatus

ABSTRACT

A method of making a lead-acid battery includes providing continuous lengths of end separator stock, positive plate stock, intermediate separator stock and negative plate stock with optional use of end separators. The separators, positive plates and negative plates are individually severed from the continuous length of stock and sequentially formed into an assembly. The assembly is introduced into a battery cell container. A plurality of assemblies may be established prior to introduction into the battery cell container. In a preferred embodiment, the assembly zone moves relative to the cutting stations for the respective continuous lengths of stock and facilitates sequential establishment of the assembly without intermediate storage of the individual separators and elements. 
     The apparatus includes equipment for supplying continuous lengths of end separator stock, positive plate stock, intermediate separator stock and negative plate stock. An assembly zone is adapted to receive the individual separator end plates from which the assembly may be introduced into a battery cell container. In one embodiment, a separator and an associated positive or negative plate may be cut substantially simultaneously. In another embodiment, they are cut individually.

This is a division, of application Ser. No. 07/464,104, filed Jan. 12,1990, now U.S. Pat. No. 4,973,335.

BACKGROUND OF INVENTION

1. Field of Invention

This invention relates to an improved method for the assembly oflead-acid batteries and an apparatus related thereto. More specifically,the invention relates to a flexible, high speed method for themanufacture of lead-acid batteries in a wide variety of sizes andconfigurations from continuous lengths of battery plate stock.

2. Description of the Prior Art

Conventional lead-acid storage batteries generally consist of aplurality of alternating flat pasted positive plates and flat pastednegative plates which are electrically insulated from one another by aporous separator material. The cell assembly so constituted is placedinto a suitable container in which the positive and negative plates arebrought into contact with a sulfuric acid electrolyte. In batteriescontaining free electrolyte, the cell assembly is generally fullyimmersed in the sulfuric acid. In batteries containing no freeelectrolyte, the sulfuric acid is fully absorbed in the plates andseparator material.

The manufacture of storage batteries of the type described hereinabove,generally involves alternately stacking cured pasted positive plates andcured pasted negative plates to form a cell assembly in which eachpositive plate is separated from each negative plate by a porousseparator material. The cell components are aligned such that all of thepositive current collecting lugs are aligned with one another. All ofthe negative current collecting lugs are aligned with one another in azone significantly separated from the plane of the aligned positivelugs. The porous separator material overlaps the plates on four sides toprovide effective electrical insulation. The positive lugs areelectrically connected to one another and the negative lugs areelectrically connected to one another by means of separate electricallyconductive plate straps. The completed cell assembly is placed in abattery container. If the battery contains more than one cell, intercellelectrical connections are then made and the battery container and coverare sealed together. The sulfuric acid electrolyte is next added to thebattery and the plates are electrochemically formed. Followingelectrochemical formation, the acid used for formation may be removedfrom the battery and replaced with sufuric acid of a different specificgravity. The battery is then washed and dried, vent caps are installed,and the final production steps are completed.

An alternative method of manufacture involves the use of individualpositive and negative plates that have been electrochemically formed,washed and dried prior to cell assembly. This method eliminates the needto electrochemically form the plates in the battery container, therebyincreasing the speed and minimizing the cost of final assembly. Thesecost savings are generally offset, however, by the added cost ofadditional handling of the very large number of individual platesinvolved prior to the cell assembly operation.

Generally, pasted battery plates are cured and, if electrochemicallyformed prior to assembly, formed as "doubles", i.e., two attached plateswhich must be separated prior to the cell assembly step. One method ofseparating paired battery plates which is disclosed in U.S. Pat. No.4,285,257, involves a rotary cutting blade which separates a stack ofpaired plates into two stacks of individual plates of the same polaritywhich represent the starting material for commonly used cell assemblyprocesses, such as those described in U.S. Pat. Nos. 4,784,380,4,720,227, 4,728,093, 4,534,549, 4,168,772, and 3,982,624. All of thesemethods and related apparatus utilize feedstock consisting of stacks ofsingular negative plates, stacks of singular porous separator pieces,and stacks of singular positive plates which are automatically combinedon a conveyor to progressively form cell assemblies containing thedesired number of positive plates, negative plates, and separator pieceswhich normally overlap the positive and negative plates on four sides.The battery cell assemblies so produced must be removed from theconveyor and the positive and negative plate lugs aligned in a separateoperation prior to the subsequent production steps of forming thepositive and negative plate straps and inserting the completed cellassembly into the battery container.

U.S. Pat. Nos. 4,479,300, 4,510,682, and 4,583,286 describe alternativemethods and apparatus for the production of a lead-acid battery cellassembly which involve building a cell assembly from a plurality ofpositive plates obtained from a source of individual positive plates, aplurality of negative plates obtained from a source of individualnegative plates, and a continuous length of porous separator materialcontaining accordion-type folds. In this construction, the positive andnegative plates are located within accordion folds and are on oppositesides of the separator from one another. The cell assemblies so producedare subjected to additional production steps in which the positive platelugs and negative plate lugs are properly aligned, the cell assembly istaped together to hold the alignment during the subsequent and separateproduction steps of forming the plate strap and inserting the taped cellassembly into the battery container.

Another known method for the production of lead-acid battery cellassemblies from stacks of singular positive plates, stacks of singularnegative plates, and a continuous length of porous separator materialinvolves properly locating a positive plate on top of a piece ofseparator material cut from said continuous length such that the lengthof the cut piece is at least twice the height of said positive plate,folding the separator material over the bottom of said positive plateand sealing it on both sides to form a 3-sided envelope, properlypositioning said negative plate relative to the envelope containing thepositive plate, and repeating these steps until the cell assemblycontains the desired number of positive and negative plates. A rotaryapparatus utilized in this production method, described in U.S. Pat. No.4,822,834, removes the aforesaid battery plates from the stacks ofindividual plates of singular polarity and positions the plates relativeto the separator and each other.

Cell assemblies produced in accordance with the above method andapparatus must be physically removed from the apparatus and subjected toseparate production steps in which the positive and negative plate lugsare aligned, the plate straps are formed, and the cell assembly isinserted into the battery container. U.S. Pat. No. 4,824,307 describes amethod and apparatus for automatically transporting and aligning saidcell assemblies prior to subjecting them to a means for forming thepositive and negative plate straps.

All of the hereinbefore described methods and apparatus involveextensive and costly handling of paired and singular plates prior tocell assembly and each requires additional production steps to align theplate lugs and insert the cell assembly into the battery container.Further, each requires a significant expenditure in dust controlequipment in order to comply with mandated lead-in-air standards whenas-cured plates are being handled.

A method and apparatus for the production of lead-acid battery cellassemblies from continuous lengths of cured battery plate stock andcontinuous lengths of separator material, is disclosed in U.S. Pat. No.4,982,482. In this method, the required lengths of a plurality of cellcomponents: e.g. a length of cured positive plate stock, a length ofporous separator material, a length of cured negative plate stock, and asecond length of porous separator material, all of which represent onlya portion of the total number of cell components in the completed cellassembly, are indexed into a cutting chamber and simultaneously cut tolength by a single cutting mechanism. The subassembly so produced isnext transported to a stationary accumulation chamber where it is storedto await the cutting and transport of the remaining portions of saidcell assembly. The process is then repeated until all of said portionsare in the stationary accumulator chamber after which the components aremoved as a unit into an alignment chamber in which the positive andnegative plate lugs are aligned and the desired degree of separatoroverlap relative to each plate is achieved. The final cell assembly alsocontains two rigid end-plates, each containing outwardly projecting"wings", which are taped tightly circumferentially in a separate stepand which, together with the plate and separator assembly, make up arigid self-contained unitized cell module which can be easily handledduring subsequent manufacturing steps which include insertion of thecell assembly into the battery container, formation of the positive andnegative plate straps, formation of intercell connectors, sealing of thetop cover to the cell container, addition of electrolyte, andelectrochemical formation of the plates in the container. Uponcompletion of formation, the battery is washed and dried and finalassembly is completed.

Although the above method eliminates the heretofore described economicand ecological problems inherent in the cutting and handling of singularand paired battery plates, it still requires that a plurality of cellsub-assemblies be fabricated and transported to, and accumulated in, astationary chamber; the final cell assembly be realigned after allsub-assemblies have been accumulated; separate rigid winged end-platesprovide cell compression and hold the cell firmly in the container, andthat the cell assembly be rigidized by taping in order to facilitatehandling during transport to, and insertion of the completed cellassembly into, the battery container. Further, the need toelectrochemically form the cured plates in the battery container priorto final assembly interrupts the smooth flow of the subsequent assemblysteps and increases the cost of manufacture.

None of these prior art cell assembly methods are adapted to achievingthe required alignment of the cell components during the cell assemblyoperation, building a cell stack and inserting the stack into thebattery container in a single continuous operation, and continuous"downstream" assembly operations that are uninterrupted by the need toelectrochemically form the plates after insertion of the cell assemblyinto the battery container. There remains, therefore, a need for apractical method of properly aligning the positive and negative platelugs during the cell assembly process, placing the completed cell stackdirectly into the battery container as the last step in the cellassembly process, and eliminating the need to electrochemically form theplates in the battery container. A process incorporating theseimprovements would substantially reduce the cost of producing lead-acidbatteries and greatly improve worker safety.

SUMMARY OF INVENTION

The present invention has met the hereinabove described needs. Theinvention provides a method for the automated manufacture of lead-acidbattery cell assemblies from continuous lengths of electrochemicallyformed battery plate stock, such as that described in U.S. Pat.Application Ser. No. 361,029 and continuous lengths of porous separatormaterial. Cell assembly is preferably achieved by cutting individualbattery plates from the continuous lengths of the electrochemicallyformed plate stock and directly transporting said individual batteryplates to a movable component assembly chamber without the need forintermediate storage. The movement of said component assembly chamber iscontrolled such that cut positive plates and cut negative plates arestacked alternately therein such that the adjacent surfaces of each cutpositive plate and each cut negative plate are separated by a cut pieceof porous separator material.

The method preferably incorporates means for properly aligning thecurrent carrying lugs of all positive plates and all negative plateswithin the component assembly chamber and means for inserting thecompleted cell assembly into the battery container without intermediatehandling, transport, or storage.

It is an object of the present invention to provide a method andapparatus for assembling lead-acid batteries from continuous lengths ofbattery plate stock, including electrochemically formed battery platestock.

It is another object of this invention to provide a manufacturing systemin which battery plates produced from continuous lengths ofelectrochemically formed battery plate stock are placed directly into acell assembly means without the need for intermediate handling,transport, or storage.

It is a further object of this invention to provide a system forproperly aligning the positive plate lugs and the negative plate lugsduring the cell assembly operation.

It is a further object of this invention to provide a means of insertinga completed cell assembly directly into a battery container withoutintermediate handling, transport, or storage.

It is a further object of this invention to provide a high speed,economical, automated method of manufacturing lead-acid batteries.

It is a further object of this invention to provide a method of makinglead-acid batteries of improved quality and consistency.

These and other objects of the invention will be more fully understoodfrom the following detailed description of the invention and referenceto the illustrations appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a portion of a continuous lengthof battery plate stock.

FIG. 2 is a front elevational view of an individual battery plate.

FIGS. 2A and 2B illustrate continuous lengths of battery plate stock andcontains indications of shapes of battery plates which may be severedtherefrom.

FIG. 3 is a schematic side elevational view of a cell assembly.

FIG. 4 is a schematic elevational view of a cell assembly extending intoa battery container.

FIG. 5 is a schematic plan illustration of a system employed inpracticing the present invention.

FIG. 6 is a partially schematic illustration of a portion of theapparatus of FIG. 5.

FIG. 7 is a plan view of a portion of the battery manufacturingapparatus with plates and separators in position.

FIG. 8 is a partially schematic illustration of a plate forming portionof the battery manufacturing apparatus of FIG. 5.

FIG. 9 is a cross-sectional illustration of a form of cutting die.

FIG. 10 is a partially schematic illustration of the cell insertionportion of the apparatus of FIG. 5.

FIG. 11 is a schematic plan view of a second embodiment of theinvention.

FIG. 11A is a partial cross-sectional view of a plate-separator lateralcombination.

FIG. 12 is a typical discharge curve produced from cycle testing of acell assembled in accordance with the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

As employed herein, the expression "electrochemically formed batteryplate stock" will refer to battery plate stock which has been subjectedto electrochemical formation sufficient to convert a substantial portionof the active material of positive plate stock to lead dioxide and asubstantial portion of the active material of negative plate stock tometallic lead.

As employed herein the expression "continuous length ofelectrochemically formed plate stock" will refer to battery plate stockthat is electrochemically formed battery plate stock and is ofsufficient size that a plurality of battery plates may be obtainedtherefrom by severing the stock at pre-determined lengths.

FIGS. 1 through 4 illustrate a lead-acid battery cell assemblycontaining positive battery plates and negative battery plates severedfrom continuous lengths of electrochemically formed plate stock andconstructed in accordance with the method of this invention.

FIG. 1 illustrates a continuous length of electrochemically formedbattery plate stock 1 from which a plurality of battery plates can besevered. Battery plate stock 1 consists of a layer of cured andelectrochemically formed battery paste 2 (of a composition selected toachieve the desired polarity of the plate stock after electrochemicalformation), which is secured to a continuous length of battery gridstrip 3. The battery grid strip 3 consists of a reticulated grid portion4, having secured thereto on one side an integral lug portion 5, and anintegral bottom border portion 6 which has an edge section 6A on theother side. The lug portion 5 may be continuous and of constant heightalong the length of grid strip 3, as shown, or may consist of a topborder portion 7 with a plurality of individual plate lugs 8 spacedperiodically along the length of said grid stock and projectingtherefrom, as shown by the broken lines in FIG. 1. The continuous gridstrip 3 may be produced by continuous casting, metal expansion ofas-cast or wrought sheet, or by any other suitable process used for theproduction of battery grid strip in relatively continuous form. Thenumber, size, shape, and pattern of the wires making up reticulated gridportion 4 may be of any desired configuration that is suitable for themanufacture of battery plates.

FIG. 2 illustrates a battery plate 9 produced by severing said platefrom a continuous length of battery plate stock 1. Battery plate 9contains an upwardly projecting lug 10 and a top border 11 which havebeen severed from lug portion 5 of battery plate stock 1, anelectrochemically formed paste portion 12 which has been severed fromthe pasted reticulated grid portion 3 of continuous battery plate stock1 and a bottom edge 13. As illustrated in FIGS. 2A and 2B, the distancebetween the bottom edge 13 of the pasted portion 12 and the top border11 of battery plate 9 may be equal to or less than the distance Hbetween the bottom edge 6A and the upper edge 5A of lug strip 5 of thecontinuous battery plate stock 1 from which the battery plate 9 wassevered.

In the form shown in FIG. 2A, the plates to be severed are shown indashed lines and will have the severed plates the full height H. Thelower edge 13 of the plate is at stock edge 6A and the upper edge of tab10 is at edge 5A.

In the form shown in FIG. 2B, the plates to be severed as shown indashed lines have tabs 10 with an upper edge below edge 5A and a loweredge 13 above edge 6A.

A cell assembly 14 constructed by the method of this invention isillustrated in FIG. 3. Cell assembly 14 has two end electricallyinsulative separators 15, a first positive battery plate 16 which hasbeen severed from a continuous length of electrochemically formedpositive battery plate stock, an intermediate electrically insulativeseparator 17, and a first negative battery plate 18 which has beensevered from a continuous length of electrochemically formed negativebattery plate stock. The plates and separators are preferably insurface-to-surface contact. The element may be further comprised ofadditional alternating positive battery plates 19 and negative batteryplates 20 which have been severed from continuous lengths ofelectrochemically formed battery plate stock and which are separated byadditional intermediate separators 21. The end separators 15 and theintermediate separators 17 and 21 are preferably composed ofcompressible fibrous porous mats such as those constructed from glass orpolymer fibers, but they may also be constructed from microporouspolymeric sheet materials such as polyethylene or polyvinylchloride, forexample. Intermediate separators 17 and 21 may have a thickness equalto, less than, or greater than the thickness of end separators 15. Endseparators 15 and intermediate separators 17 and 20 may extend beyondthe top edge, bottom edge, and both side edges of battery plates 16, 18,19, and 20; or beyond only the top edge and the bottom edge of saidbattery plates while being flush with the two side edges; or beyond onlyone edge of the positive and negative battery plates while being flushwith the remaining three edges of said plates.

FIG. 4 illustrates a cell assembly 14 partially inserted into a batterycontainer 21 in a manner such that all of the positive battery platelugs 22 are properly aligned, all of the negative battery plate lugs 23are properly aligned, and the aligned positive plate lugs and alignednegative plate lugs are properly situated within the cell assembly sothat formation of the positive plate straps and negative plate strapscan be achieved without further movement of said plate lugs. Alignedlugs 22 are laterally spaced from aligned lugs 23.

The present invention provides a single integrated continuous method ofmanufacturing a lead-acid battery cell assembly of the type heretoforedescribed and inserting said assembly into a battery container whichpreferably includes the steps of:

(a) Severing an individual piece of battery end separator material froma continuous length of porous end separator stock to form an endseparator, directly transporting the end separator to a mobile cellassembly chamber which has been positioned to receive the end separator,and inserting said end separator into the mobile cell assembly chamber;and

(b) Severing an individual piece of positive battery plate stock from acontinuous length of electrochemically formed positive battery platestock to form a positive battery plate, directly transporting thepositive battery plate to the mobile cell assembly chamber which hasbeen positioned to receive the positive battery plate, and inserting thepositive battery plate into said mobile cell assembly chamber such thatis is adjacent to the end separator and accurately positioned such thatthe lug portion of said positive battery plate will be properly alignedwith the lug portion of any additional positive battery plates which maysubsequently be inserted into the mobile cell assembly chamber; and

(c) Severing an individual piece of battery intermediate separatormaterial from a continuous length of porous intermediate separator stockto form an intermediate separator, directly transporting theintermediate separator to the mobile cell assembly chamber which hasbeen positioned to receive the intermediate separator, and inserting theintermediate separator into the mobile cell assembly chamber; and

(d) Severing an individual piece of negative battery plate stock from acontinuous length of electrochemically formed negative battery platestock to form a negative battery plate, directly transporting saidnegative battery plate to the mobile cell assembly chamber which hasbeen positioned to receive said negative battery plate, inserting saidnegative battery plate into the mobile cell assembly chamber such thatis is adjacent to the aforesaid intermediate separator and accuratelypositioned such that the lug portion of the negative battery plate willbe properly aligned with the lug portion of any additional negativebattery plates which may subsequently be inserted into said mobile cellassembly chamber. Step (a) is repeated with end separator placedadjacent to the exterior of said negative battery plate.

FIGS. 5 through 10 illustrate in greater detail various aspects of themethod of manufacturing a cell assembly 14.

Referring to FIGS. 5 and 6, the materials from which the components ofcell assembly 14 are produced include a continuous length of porous endseparator material 24, a continuous length of electrochemically formedbattery plate stock of a first polarity 25, a continuous length ofporous intermediate separator material 26, a continuous length ofelectrochemically formed battery plate stock of a second polarity 27,and a battery container 28. It is preferred that said continuous lengthsof end separator material and intermediate separator material be in theform of coils or traverse wound spools and that said coils or spools bepositioned on uncoiling means 29 and 30, respectively. The axes of thecoils or spools may be essentially vertical, essentially horizontal, orinclined at a convenient angle therebetween. It is preferred that saidcontinuous lengths of positive and negative battery plate stock be inthe form of coils and that said coils be, positioned on uncoiling means31 and 32, respectively, such that the axis of each coil is essentiallyvertical and the lug strip 5 is positioned in a generally downwarddirection.

The uncoiling means for the battery plate stock and for the separatormaterials may be powered in order to control the length of materialuncoiled at a specific time or unpowered such that the length ofmaterial uncoiled at a specific time is controlled by another mechanism.

Construction of cell assembly 14 and the insertion of said cell assemblyinto battery container 28 are accomplished in a single continuousoperation utilizing a cell assembly means 33 comprised of an endseparator fabrication station 34, a first polarity plate fabricationstation 35, an intermediate separator fabrication station 36, a secondpolarity plate fabrication station 37, a mobile cell assembly chamber 38containing a battery container support means 39, and a battery containerloading station 40.

In addition to a battery container support means 39, the mobile cellassembly chamber 38 contains an enclosure 41 into which the individualseparator pieces and battery plates are sequentially placed and analignment means that positions the first polarity plates and the secondpolarity plates such that the lugs of the first polarity plates 22(shown in FIG. 4 as positive plate lugs 22) and the lugs of the secondpolarity plates 23 (shown in FIG. 4 as negative plate lugs 23) areproperly aligned and do not have to be repositioned prior to fabricationof the positive and negative plate straps which will be secured to them.Further, the alignment means position said plates of opposite polarityrelative to separators 15, 17, 21 (see FIG. 3) such that the desireddegree of separator overlap is achieved. One such alignment means,illustrated in FIG. 5, consists of retractable plate alignment pins 42which are inserted into the cell assembly enclosure 41 prior tointroduction of said battery plates therein. The alignment pins 42 maybe retracted from the enclosure after all of the cell components havebeen placed therein and prior to insertion of said cell assembly intothe battery container 28. Insertion of said alignment pins into theenclosure 41, and retraction therefrom, may be accomplished by the useof an air-actuated cylinder or mechanical means well known to thoseskilled in the art.

The battery container support means 39 positions the battery container28 such that the open end of said container faces the cell assemblyenclosure 41 and is aligned therewith such that the cell assembly 14 maybe inserted snugly into the battery container 28 without damage to anyof the cell components as disclosed hereinafter.

The mobile cell assembly chamber 38 is provided with indexing means suchthat it may be sequentially transported to, and aligned with,fabrication stations 34, 35, 36, 37, and 40. The indexing means may becomprised of air actuated cylinders 38A and mechanical stops mounted toslide mechanism 48, as shown in FIG. 5, a mechanical cam-activateddrive, or any other mechanism capable of providing the desired motion.Suitable controls for effectuating such coordinated motion will be wellknow to those skilled in the art.

With continued reference to FIGS. 5 and 6, an individual end separator15 is first fabricated by removing a length of continuous separatormaterial equal to the height of said end separator from coil 24, whichhas been positioned on uncoiler 29, by means of stock feeder 43 whichpushes the desired length of material onto a cutting table 44 which isan integral part of the end separator fabrication station 34. The porousseparator material indexed onto said cutting table is held firmly inposition by a pick-up head 45 and simultaneously acted upon by a cuttingmeans which severs the continuous length to form said individual endseparator. A preferred cutting means, illustrated in FIG. 6, consists ofa mobile shear blade 46 positioned in a slot 47, located between thecutting table 44 and the stock feeder 43, which severs the continuousseparator material with an upward motion while said separator materialis being held securely in place by said pick-up head and said stockfeeder 43. The height of the individual end separator 15 is controlledby the length of continuous separator material indexed onto the cuttingtable 44 and the width of said separator is equal to the width of thecontinuous separator material removed from coil 24.

Once severed, the individual end separator 15 is lifted by the pick-uphead 45, which is connected to a vacuum means (not shown) through achannel 45A contained therein, transported (dotted lines) to a positiondirectly above the cell assembly enclosure 41 in the mobile cellassembly chamber 38 which has been indexed into position adjacent to theend separator fabrication station 34, and placed therein by a downwardmotion of said pick-up head and removal of the vacuum from channel 46.The vacuum line may next be slightly pressurized with air to assist withremoval of the end separator from the pick-up head. The pick-up head 45is then retracted in an upward direction, transported to a positiondirectly above the cutting table 44 and moved vertically downward untilit is securely in contact with the next segment of the continuousseparator material which has been indexed onto the cutting table fromcoil 24, and the mobile cell assembly chamber 38 is indexed to aposition adjacent to the first polarity plate fabrication station 35.The above cycle is repeated when the mobile cell assembly chamber 38 isnext indexed into position adjacent to the end separator fabricationstation 34. The vertical and lateral movements of the pick-up head 45may be achieved by means of air-actuated cylinders 45B, 45C (FIG. 6), ormechanical means such as a cam-activated drive. The stock feeder means43 may be of a reciprocating type, such as that shown in FIG. 5, aroll-actuated type, a tractor-activated type, or any other type whichcan be used to consistently deliver a specified length of separatormaterial onto the cutting table 44.

If end separator 15 is sized to overlap the positive and negative platesin the cell assembly, the length and width dimensions of said separatorsar greater than the distances between the retractable alignment pins 42in the cell assembly enclosure 41 such that, when the separators areplaced into said enclosure, portions of said separators are temporarilydeformed in the vicinity of each locating pin 42 as illustrated in FIG.7. The positive and negative plates are shown underlying separator 21.

The second step in the cell assembly process involves the fabrication ofa battery plate of a first polarity from a continuous length ofelectrochemically formed battery plate stock, transport of said batteryplate to mobile cell assembly chamber 38, and insertion of said batteryplate into said cell assembly chamber.

With reference to FIGS. 1, 2A, 3, 5, and 8, an individual battery plate9 is fabricated by indexing a continuous length of electrochemicallyformed battery plate stock 1 of a first polarity, which may be in theform of a coil 25, through a lug cleaning station 49 (FIG. 8) in whichthe lug strip portion 5 of said battery plate stock is cleaned to removeloose dried battery paste and residual oxides. Such paste and residualoxides are created during the preceding curing and electrochemicalformation processes. A specified length of said battery plate stockequal to the width of the individual battery plate 9 of first polarityto be fabricated is transported onto cutting table 50 by means of stockfeeder 51. It is preferred that said continuous length of battery platestock be oriented vertically as it traverses the lug cleaning station 49and that the cleaned plate stock exiting the lug cleaning station bereoriented prior to entering the stock feeder 51 (FIG. 5) such that themajor pasted surfaces of the plate stock indexed onto the cutting table50 are positioned parallel to the surface of said cutting table.

The indexed length of battery plate stock is next acted upon by acutting means which severs said individual battery plate from saidcontinuous length such that said battery plate is comprised of a pastedportion 12 and an accurately positioned lug portion 10. A preferredcutting means is comprised of a mobile cutting die 52, which may beshaped as indicated by the broken lines in FIGS. 2 or FIG. 2A,positioned in a slot of generally similar shape 53 located in thecutting table 50. In this instance the cutting die severs the continuousplate stock with an upward motion while said plate stock is being heldsecurely in place on the cutting table 50 by pick-up head 54 (FIG. 8)which contains a circumferential retractable portion 54A opposed to thecutting die.

A second preferred cutting means, illustrated in FIG. 9, is comprised ofa rigid cutting die 55 mounted circumferentially relative to pick-uphead 54 and adapted to reciprocate in the direction shown by the arrowsand opposed to the surface of the cutting table 50 which severs thecontinuous plate stock 1 with a downward motion when said cutting dieand said pick-up head are brought into contact with said plate stock. Inthis configuration, the pick-up head 54 is equipped with a means whichpermits an independent vertical motion relative to the rigid cutting die55.

Once severed, the individual battery plate of first polarity is liftedby the pick-up head 54, which is connected to a vacuum means not shown)through channel 56 contained therein and transported laterally to aposition directly above the cell assembly enclosure 41 in the cellassembly chamber 38 which has been indexed into a position adjacent tothe first polarity plate fabrication station 35 (FIG. 5). The pick-uphead 54 is next rotated 90 degrees by a rotation means (not shown) suchthat the battery plate lug is oriented towards the cutting table 50 andsaid individual battery plate is placed into said cell assemblyenclosure by a downward motion of said pick-up head and removal of thevacuum from channel 56. The vacuum line may be slightly pressurized toassist removal of the battery plate from the pick-up head. Precisepositioning of said individual battery plate is achieved by means ofbattery plate alignment pins 42, as illustrated in FIG. 7.

The pick-up head 54 is next retracted in an upward direction andtransported to a position directly above the cutting table 50 and themobile cell assembly chamber 38 is indexed to a position adjacent to theintermediate separator fabrication station 36, and the above cycle maybe repeated when the mobile cell assembly chamber 38 is next indexedinto position adjacent to the first polarity plate fabrication station35.

The vertical and lateral movements of the pick-up head 54 andcircumferentially retractable portion 54A, may be achieved by means ofair-actuated cylinders 45D, 45E, 45F and 45G or mechanical means such asa cam-activated drive. The stock feeder means may be of a reciprocatingtype, as illustrated in FIG. 5, a roll-type, a tractor-feed type, or anyother type which can be used to consistently deliver a specified lengthof continuous battery plate stock onto the cutting table 50. The firstpolarity plate fabrication station 35 also contains a means for removalof scrap generated during the plate severing operation (not shown).

The third step in the cell assembly process, which involves fabricationof an individual intermediate separator from a continuous length ofintermediate battery separator stock and insertion of said individualintermediate separator into cell assembly chamber, is essentially thesame as that heretofore described pertaining to the fabrication,transport, and insertion of the individual end separator.

In general, the subsequent cycles of operating will be generallyidentical to the previously described procedures with respect to theseparator and battery plate stock handling and, as a result, will not bedescribed in detail.

With reference to FIGS. 3, 5 and 6, an individual intermediate batteryseparator 17 is fabricated by removing a length of continuous separatormaterial equal to the height of said intermediate separator from coil26, which has been positioned on uncoiler 30, by means of stock feeder57 which pushes the desired length of material onto a cutting table 58which is an integral part of the intermediate separator fabricationstation 36. With reference to FIG. 6, the porous separator materialindexed onto said cutting table is held firmly in position by a pick-uphead identical to pickup head 45 and simultaneously acted upon by acutting means which severs the continuous length to form the individualintermediate separator 17 (see FIG. 2). A preferred cutting meansconsists of a mobile shear blade such as a blade identical to blade 46positioned in a slot, located between the cutting table 58 and the stockfeeder 57. The blade severs the continuous separator material with anupward motion while said separator material is being held securely inplace by said pick-up head and said stock feeder. The height of theindividual intermediate separator 17 is controlled by the length ofcontinuous separator material indexed onto the cutting table 58 and thewidth of said separator is equal to the width of the continuousseparator material removed from coil 26.

Once severed, the individual intermediate separator 17 is lifted by thepick-up head which is connected to a vacuum means through a channelcontained therein, transported laterally to a position directly abovethe cell assembly enclosure 41 in the mobile cell assembly chamber 38which has been indexed into position adjacent to the intermediateseparator fabrication station 36, and placed therein by a downwardmotion of said pick-up head and removal of the vacuum from the channel.The vacuum line may next be slightly pressurized with air to assistremoval of the intermediate separator from the pick-up head. The pick-uphead is then retracted in an upward direction, transported laterally toa position directly above the cutting table 58 and moved verticallydownward until it is securely in contact with the next segment of thecontinuous separator material which has been indexed onto the cuttingtable from coil 26, and the mobile cell assembly chamber 38 is indexedto a position adjacent to the second polarity plate fabrication station37. The above cycle may be repeated when the mobile cell assemblychamber 38 is next indexed into position adjacent to the end separatorfabrication station 34. The vertical and lateral movement of the pick-uphead may be achieved by means of air-actuated cylinders or mechanicalmeans such as a cam-activated drive. The stock feeder means 57 may be ofa reciprocating type, as illustrated in FIG. 5, a roll-actuated type, atractor-actuated type, or any other type which can be used toconsistently deliver a specified length of separator material onto thecutting table 58.

If end separator 15 and intermediate separator 17 are sized to overlapthe positive and negative plates in the cell assembly, the length andwidth dimensions of said separators are greater than the distancesbetween the retractable plate alignment pins 42 in the cell assemblyenclosure 41 such that, when the separators are placed into saidenclosure, portions of said separators are temporarily deformed in thevicinity of each locating pin, as shown in FIG. 7.

The fourth step in the cell assembly process, which involves thefabrication of an individual battery plate of a second polarity from acontinuous length of electrochemically formed battery plate stock,transport of said battery plate to mobile cell assembly chamber 38, andinsertion of said battery plate into said cell assembly chamber, isessentially the same as that heretofore described pertaining to thefabrication, transport, and insertion of the individual battery plate ofa first polarity.

With reference to FIGS. 1, 2A, 5 and 8, an individual battery plate 9 ofa second polarity is fabricated by indexing a continuous length ofelectrochemically formed battery plate stock 1, which may be in the formof a coil 27, through a lug cleaning station such as 61 in which the lugstrip portion 5 of said battery plate stock is cleaned to remove loosedried battery paste and residual oxides created during the precedingcuring and electrochemical formation processes, and transporting aspecified length of said battery plate stock equal to the width of theindividual battery plate of a second polarity to be fabricated ontocutting table 62 (FIG. 5) by means of stock feeder 63. It is preferredthat the continuous length of battery plate stock be oriented verticallyas it traverses the lug cleaning station and that the cleaned platestock exiting said lug cleaning station be reoriented prior to enteringthe stock feeder 63 such that the major pasted surfaces of the platestock indexed onto the cutting table 62 are positioned parallel to thesurface of said cutting table.

The indexed length of battery plate stock is next acted upon by acutting means which severs said individual battery plate from saidcontinuous length such that said battery plate is comprised of a pastedportion 12 and an accurately positioned lug portion 10 positioned suchthat, when said battery plate is placed into the mobile cell assemblychamber 38, all of the lugs of the second polarity are properly alignedand situated relative to the aligned lugs of the first polarity suchthat formation of the individual plate straps connecting lugs of commonpolarity can be formed without further movement of said plate lugs.

A preferred cutting means is generally identical to that of the typeshown in FIG. 8 and has a mobile cutting die 64 (FIG. 5), which may besimilar to mobile cutting die 52 (FIG. 8) and may be shaped as indicatedby the broken lines in FIGS. 2 or FIG. 2A, positioned in a slot 65 (FIG.5), of similar shape located in the cutting table. In this instance saidcutting die severs the continuous plate stock with an upward motionwhile said plate stock is being held securely in place on the cuttingtable by pick-up head which may be identical to pick-up head 54 (FIG. 8)which contains a circumferential retractable portion which may beidentical to retractable portion 54A (FIG. 8) opposed to said cuttingdie. A second preferred cutting means which may be identical to thatshown in FIG. 9, is comprised of a cutting die which may be identical tocutting die 55 mounted circumferentially relative to pick-up head whichmay be identical to pick-up head 54 and opposed to the surface of thecutting table 62 which severs the continuous plate stock with a downwardmotion when said cutting die and said pick-up head are brought intocontact with said plate stock. In this configuration, the pick-up headis equipped with a means that permits an independent vertical motionrelative to the rigid cutting die.

Once severed, the individual battery plate 9 of a second polarity islifted by the pick-up head, which is connected to a vacuum means andtransported laterally to a position directly above the cell assemblyenclosure 41 in the cell assembly chamber 38 which has been indexed intoa position adjacent to the second polarity plate fabrication station 37.The pick-up head is next rotated 90 degrees by a rotation means (notshown) such that battery plate lug 10 is oriented towards the cuttingtable 62 and said individual battery plate is placed into said cellassembly enclosure by a downward motion of said pick-up head and removalof the vacuum. The vacuum line may be slightly pressurized with air toassist removal of the battery plate from the pick-up head. Precisepositioning of said individual battery plate is achieved by means ofbattery plate alignment pins 42, as illustrated in FIG. 7.

The pick-up head is next retracted in an upward direction, returned to aposition directly above the cutting table 62, and the mobile cellassembly chamber 38 is indexed to a position adjacent to theintermediate separator fabrication station 36 or end separatorfabrication station 34 depending upon the specific cell constructionderived. The above cycle may be repeated when the mobile cell assemblychamber 38 is next indexed into position adjacent to the second polarityplate fabrication station 37.

The vertical and lateral movements of the pick-up head may be achievedby means of air-actuated cylinders or mechanical means as is well knownto those skiled in the art. The stock feeder means may be of areciprocating type such as is illustrated in FIG. 5, a roll-type, atractor-feed type, or any other type which can be used to consistentlydeliver a specified length of continuous battery plate stock onto thecutting table. The second polarity plate station 37 also contains ameans for removing any scrap generated during the plate severingoperation.

The hereinabove described sequence of fabricating, transportingindividual intermediate separators, individual plates of a firstpolarity, individual plates of a second polarity, and an individual endseparator is repeated until a completed cell assembly consisting of anydesired number of alternating plates of a first polarity and plates of asecond polarity separated by intermediate separators and two endseparators has been obtained.

Upon completion of the aforesaid sequence, the cell assembly chamber 38(FIGS. 5, 6 and 10) is indexed adjacent to the cell insertion station40. With reference to FIG. 10, the completed cell assembly is acted uponin a downwardly direction by a compression means 69 such that thecompressed cell assembly is 14 aligned with the top opening of thebattery container 28 which is disposed in the battery container supportsection 39 of mobile cell assembly chamber 38. The length and width ofsaid compressed cell assembly are less than the equivalent length andwidth dimensions of the top opening of said battery container. Thebattery plate alignment pins 42 are retracted by a pin retraction means59 such as an air-actuated cylinder 68. The compressed cell assembly isnext acted upon in a horizontal direction by a reciprocating insertionmeans 70 which slides said cell assembly laterally relative tocompression means 69 and inserts said cell assembly into the batterycontainer 28. Compression means 69 and cell insertion means 70 are nextretracted, the battery container and the cell assembly therein areremoved from the mobile cell assembly chamber 38, a new container isinserted into the battery container support means 39, and the cycle isrepeated.

Although a single cell battery container 28 has been used in the aboveillustration, it will be obvious to those skilled in the art that themethod of this invention may also be used to fill multi-cell batterycontainers by mounting the battery container support means 39 upon avertical indexing means which sequentially positions said multi-cellbattery container such that the partitioned volume into which the cellassembly is to be inserted is properly aligned with the cell assemblyenclosure 41.

The sequence and speed of all of the operations involved in the methodof battery cell assembly heretofore described may be controlled by anysuitable means such as a programmable controller such as Model SLC-100produced by the Allan Bradley Company.

As illustrated in FIG. 4, which shows a cell assembly patially insertedinto a battery container, the aforesaid procedure results in acompressed cell in which all plate lugs of a first polarity and allplate lugs of the opposite polarity are aligned such that the assembledcell can be subjected to a subsequent plate strap formation step withoutfurther positioning of the plates within said assembly.

In yet another embodiment of this invention, the number of steps andtime involved in building a complete battery cell assembly is greatlyreduced by simultaneously processing a continuous length of porousseparator material and a continuous length of electrochemically formedbattery plate stock.

Referring to FIG. 11, this embodiment involves:

(a) Indexing a length of continuous porous battery separator stock 24into end separator station 34 and severing and transporting the same.The separator is inserted into the mobile cell assembly chamber 38,using the methods heretofore described for end separators andintermediate separators. The mobile cell assembly chamber is indexed toa position adjacent to the first polarity plate fabrication station 35by means of air cylinder 38B; and

(b) Aligning a second continuous length of porous battery separatorstock 26 vertically above and in contact with a continuous length ofelectrochemically formed battery plate stock of a first polarity 25 suchthat said separator stock overlaps both longitudinal edges of saidbattery plate stock to the degree desired; and

(c) Simultaneously indexing equal lengths of the aforesaid secondseparator stock and battery plate stock onto cutting table 50 of thefirst polarity plate fabrication station 35 and simultaneously severing,transporting, and inserting the separator and battery plate thus formedinto the mobile cell assembly chamber 38, using the methods heretoforedescribed for processing battery plates of both polarities, and indexingsaid mobile cell assembly chamber to a position adjacent to the secondpolarity plate fabrication station 37; and

(d) As shown in FIGS. 11 and 11A, aligning a third continuous length ofporous battery separator stock 72 vertically above a continuous lengthof electrochemically formed battery plate stock of a second polarity 27such that said separator stock overlaps both longitudinal edges of saidbattery plate stock to the degree desired; and

(e) Simultaneously indexing equal lengths of the aforesaid thirdseparator stock and second polarity battery plate stock onto cuttingtable 62 of second polarity plate fabrication station 37 andsimultaneously severing, transporting, and inserting the separator andbattery plate thus formed into the mobile cell assembly chamber 38,using the methods heretofore described for processing battery plates ofboth polarities, and indexing the mobile cell assembly chamber to firstpolarity plate fabrication station 50 (or to cell insertion station 40if the cell assembly being produced only contains two plates of oppositepolarity); and

(f) Sequentially repeating steps 4 and 5 until the desired number ofalternating plates of first and second polarity each separated by aporous separator have been placed in the aforesaid mobile cell assemblychamber; and

(g) Indexing said mobile cell assembly chamber to the cell insertionstation 40 in which the cell assembly is compressed and inserted intocell container 28 as heretofore described.

The use of this embodiment greatly increases the speed of assembly bycombining two processing steps into a single step in which one separatorand one plate are processed simultaneously.

Cell assemblies produced using this second embodiment are characterizedby plates and separators of identical width such that the the side edgesof said separators and said battery plates are flush with one another.In order for the separators to overlap the top border of the plates to adesired degree, it is necessary to pre-punch the lug portion of theplate in lug punch stations 70 and 73 (FIG. 11) and to sever the batteryplate and separator combination from the continuous lengths of platestock and separator stock by means of a sole transverse cut across theentire width of said plate stock and separator stock in platefabrication stations 35, 37. The distance by which each separatoroverlaps each plate on the bottom edge is controlled by the relativewidths and alignment of the plate stock and separator stock that areindexed into said plate fabrication stations.

While the hereinabove discussion and illustrations of the method of thisinvention have been restricted to an apparatus having only a single endseparator fabrication station, a single positive plate fabricationstation, a single intermediate separator fabrication station, a singlenegative plate fabrication station, and a single reciprocating cellassembly chamber, it will be apparent to those skilled in the art thatone may practice the invention using an apparatus containing a pluralityof cell assembly chambers which move in only one direction relative to aplurality of end separator fabrication stations, positive platefabrication stations, intermediate separator fabrication stations, andnegative plate fabrication stations, the number of each of said stationsbeing equal to the number of end separators, positive plates,intermediate separators, and negative plates, respectively, contained inthe finished cell assembly. The aforesaid plurality of cell assemblychambers my be indexed in a rotary manner or in a straight line mannerpast a series of adjacent separator and plate fabrication stations.

While for convenience the above discussion and illustrations have madereference to specific configurations, polarities, and assembly steps, itwill be apparent to those skilled in the art that one may practice theinvention employing other configurations, relative polarities and platepositions, and assembly conditions. Also, if desired, the invention maybe practiced without the use of end separators in the cell assembly.

The following example provides specific preferred practices in employingthe methods of this invention.

EXAMPLE

This example illustrates that lead-acid battery cell assemblies can beproduced automatically by means of the method of this invention and thatbatteries made therefrom are equivalent in capacity and performance tosimilar batteries assembled by hand.

Seventy-three lead-acid battery cell assemblies were produced using anautomated cell assembly apparatus having of an end separator fabricationstation, a positive plate fabrication station, an intermediate separatorfabrication station, a negative plate fabrication station, a cellinsertion station, and a reciprocating mobile cell assembly chambercontaining an integral battery container support section. The stationsand cell assembly chamber were positioned relative to one another asillustrated in FIG. 5.

Each cell assembly consisted of two 2.10"L×1.41"H×0.078" porousmicrofiber glass mat end separators; four 1.79"L×1.26"H×0.087"T positiveplates, six 2.10"L×1.41"H×0.086"T porous microfiber glass matintermediate separators, and three 1.79"L×1.26"H×0.077"T negativeplates. Each positive plate and each negative plate contained a0.188"L×0.100"W and 0.035"T lug portion protruding outwards from the topborder portion thereof. Each positive plate contained approximately 8.5grams of electrochemically formed positive active material. Eachnegative plate contained approximately 6.9 grams of electrochemicallyformed negative active material. Each completed cell assembly wasinserted into a single cell polypropylene battery container such thatapproximately 25% of the height of the cell assembly protruded from thetop of the container in order to facilitate formation of the positiveand negative plate straps in a subsequent operation. The interiordimensions of the top opening of each battery container wereapproximately 1.97"×0.910", the interior depth was 1.56", the wallthickness was approximately 0.035", and each wall of the container had adraft angle of approximately 1°.

The end separator fabrication station and the intermediate separatorfabrication station of the automated cell assembly apparatus wereessentially the same as those described previously and illustrated inFIGS. 5 and 6. Each station included a cutting table, a reciprocatingstock feeder, and upwardly acting shear blade, and a pickup/transporthead positioned so as to be directly above the cutting table when in theretracted position and to be directly above the aforesaid mobile cellassembly chamber when in the extended position.

The positive and negative plate fabrication stations were modified fromthose previously described to accommodate pre-cut, pre-cleanedelectrochemically formed battery plates which were used to simulateplates severed from continuous lengths of cleaned positive and negativeplate stock. Each station contained a upwardly acting plate feedingmagazine and a pick-up/transport head positioned so as to be directlyabove said magazine when in the retracted position and directly abovethe aforesaid mobile cell assembly chamber when in the extendedposition.

In a separate experiment, it was determined that individualelectrochemically formed positive and negative battery plates, eachhaving a pre-formed top border and lug protruding outwardly therefrom,could be satisfactorily severed from a length of electrochemicallyformed battery plate stock containing five such plates, each measuringabout 1.79"×1.26" and each containing a 0.188"×0.100"×0.035" lug. Thepositive plates were approximately 0.087" thick. The negative plateswere approximately 0.077" thick. The hardened steel cutting toolemployed to sever the plates was ground so as to have an included angleof 5° to 7° between the intersecting surfaces which formed the cuttingedge of said tool.

Pre-cut electrochemically formed positive plates similar to thosedescribed hereinabove were placed into the positive plate feedingmagazine and pre-cut, electrochemically formed negative plates similarto those described above were placed into a negative plate feedingmagazine. The magazines were positioned in their respective stationssuch that an individual pre-cut plate was presented to thepick-up/transport head at precisely the same location and height aswould have been the case if each plate had been severed from acontinuous length of plate stock at that location. The lugs of all ofthe positive and negative plates had been pre-cleaned by wire brushingprior to insertion into said magazines. In order to simulate the lugorientation step described previously, all positive plates were placedin the positive magazine such that the plate lugs faced away from themobile cell assembly chamber and were towards the left side of themagazine, whereas all negative plates were placed in the negativemagazine such that the lugs faced away from the mobile cell assemblychamber and were towards the right side of the magazine. The operationof the plate fabrication stations involved removal of the topmost platefrom a vertical stack of plates in the magazine and moving the remainingplates vertically upward until the top surface of the uppermost plateremaining in the magazine was positioned essentially in the same planeas was the top surface of the plate which had just been removed from themagazine. The upward motion of the plate stack in the magazine wasprovided by a commercially available air-over-oil cylinder. The heightto which the plate stack was raised was controlled by an electric eyepositioned so as to halt the upward motion of the cylinder when thetopmost surface of the top plate in the magazine reached the desiredlevel.

The vertical movement of each pick-up/transfer head in the cell assemblyapparatus was imparted by means of commercially available air-activatedcylinders, whereas the horizontal movement of said pick-up/transfer headwas imparted by means of commercially available air-activated slides.All cylinders and slides were controlled by a series of solenoids andpneumatic valves. A vacuum created by the use of a single commerciallyavailable vacuum pump attached in series with a vacuum accumulator tankand applied to each pick-up/transport head imparted the force requiredto hold the component firmly to said pick-up head. Removal of the vacuumfrom the pick-up head allowed the plates and separators to be releasedonce placed in the mobile cell assembly chamber. The mobile cellassembly chamber of the cell assembly apparatus was essentially the sameas that previously described and contained a cell assembly section intowhich retractable plate alignment pins were inserted and a batterycontainer support section which properly aligned a battery containertherewith.

The battery container was placed in said container support section onits side such that the open top of the container faced said assemblysection. The movement and proper positioning of the mobile assemblychamber relative to each fabrication station was provided by means oftwo commercially available 3-position air-activated cylinders, as shownin FIGS. 5 and 11. The first cylinder controlled both the movement ofthe mobile cell assembly chamber and its proper alignment with the cellinsertion station, the end separator fabrication station, and thepositive plate fabrication station. The second cylinder controlledalignment of the cell assembly chamber with the intermediate separatorfabrication station and the negative plate fabrication station byaccurately placing a positive stop at the desired station against whichthe cell assembly unit was positioned by movement of the first cylinder.The insertion of the retractable plate alignment pins into the cellassembly section and the retraction therefrom was accomplished by meansof a commercially available air-actuated cylinder.

The cell insertion station of the automated cell assembly apparatus wasessentially the same as that previously described and contained adownwardly moving compression member which compressed the completed cellassembly such that the compressed height of said assembly was less than0.910", a downwardly moving pin retraction member which engaged thesteel plate to which all of the retractable battery plate alignment pinswere attached and pulled it downwards until all of the pins wereretracted from the cell assembly section, and a forwardly movinginsertion member which displaced the compressed cell assemblyhorizontally and caused it to be inserted into the battery container.The vertical motions of the compression member and the pin retractionmember were imparted by means of commercially available air-activatedcylinders. The horizontal motions of the insertion member were impartedby means of a commercially available air-activated slide device. All ofthe aforesaid air-activated devices were controlled by a series ofsolenoids and pneumatic valves.

The sequence and speed of all of the motions described above werecontrolled by a commercially available programmable controller.

The sequential steps followed in the automatic production of theaforesaid 73 lead-acid battery cell assemblies were, as follows:

(a) A single cell battery container was manually placed into the batterycontainer support section of the mobile cell assembly chamber; and

(b) The automatic cycle was begun by depressing the "Start" button onthe automated cell assembly device, (Note: All steps described hereafteroccurred automatically.); and

(c) The mobile cell assembly chamber was indexed into position adjacentto the cell insertion station, the retractable battery plate alignmentpins were inserted into the cell assembly section of said chamber, andthe mobile cell assembly chamber was indexed into position adjacent tothe end separator fabrication station; and

(d) A 1.41" length of 2.10"W and 0.078"T porous microfiber glass mat endseparator was indexed onto the cutting table of the end separatorfabrication table; the pick-up/transport head was moved verticallydownward to contact the separator and a vacuum was applied to said head;the separator was cut to length by the upward movement of the shearblade; the pick-up/transport head was next moved in an upwardsdirection, then moved horizontally until it was positioned directlyabove the mobile cell assembly chamber, and then moved verticallydownwards until the severed separator was placed firmly into saidassembly chamber; the vacuum was eliminated by bringing air into thevacuum channel in the pick-up/transport head which was then movedvertically upwards and then horizontally until it returned to itsoriginal position; and the mobile cell assembly chamber was indexed intoposition adjacent to the positive plate fabrication station; and

(e) The pick-up/transport head of the positive plate fabrication stationwas moved in downwardly direction until it contacted the upper surfaceof the uppermost 1.79"×1.26"×0.087" positive plate in the positive platemagazine; a vacuum was applied to said pick-up/transport head; thepick-up/transport head was next moved in an upwards direction, thenmoved horizontally until it was positioned directly above the mobilecell assembly chamber, and then moved vertically downwards until thepositive plate was placed firmly between the battery plate alignmentpins in said assembly chamber; the vacuum was eliminated by bringing airinto the vacuum channel in the pick-up/transport head which was nextmoved vertically upwards and then horizontally until it returned to itsoriginal position: and the mobile cell assembly chamber was indexed intoposition adjacent to the intermediate separator fabrication station; and

(f) A 1.41" length of 2.10"W and 0.086"T porous microfiber glass matintermediate separator was indexed onto the cutting table of theintermediate separator fabrication table; the pick-up/transport head wasmoved vertically downward to contact the separator and a vacuum wasapplied to said pick-up head; the separator was cut to length by theupward movement of the shear blade; the pick-up/transport head was nextmoved in an upwards direction, then moved horizontally until it waspositioned directly above the mobile cell assembly chamber, and thenmoved vertically downwards until the severed separator was placed firmlyinto said assembly chamber; the vacuum was eliminated by bringing airinto the vacuum channel in the pick-up/transport head which was thenmoved vertically upwards and then horizontally until it returned to itsoriginal position; and the mobile cell assembly chamber was indexed intoposition adjacent to the negative plate fabrication station; and

(g) The pick-up/transport head of the negative plate fabrication stationwas moved in downwardly direction until it contacted the upper surfaceof the uppermost 1.79"×1.26"×0.077" negative plate in the negative platemagazine: a vacuum was applied to said pick-up/transport head; thepick-up/transport head was next moved in an upwards direction, thenmoved horizontally until it was positioned directly above the mobilecell assembly chamber, and then moved vertically downwards until thenegative plate was placed firmly between the battery plate alignmentpins in said assembly chamber such that the lug of the negative platewas positioned on the side of the cell assembly chamber opposite to theside containing the positive plate lug; the vacuum was eliminated bybringing air into the vacuum channel in the pick-up/transport head whichwas next moved vertically upwards and then horizontally until itreturned to its original position: and the mobile cell assembly chamberwas indexed into position adjacent to the intermediate separatorfabrication station; and

(h) Step (f) was next repeated; and

(i) Steps (e), (f), (g), and (a) were next repeated in sequence suchthat a cell assembly containing two end separators, four positiveplates, three negative plates, and six intermediate separators eachpositioned between one positive plate and one negative plate, wasobtained after which the mobile cell assembly chamber was indexedadjacent to the cell insertion station; and

(j) The cell compression member of the cell insertion station was nextmoved vertically downwards into the cell assembly chamber until the cellassembly was compressed to a height of about 0.850"; the battery platealignment pins were retracted from the cell assembly chamber; and thecell insertion member was moved horizontally towards the batterycontainer until the compressed cell assembly was inserted into thebattery container such that approximately 75% of the height of saidassembly was inserted into said container; the cell compression memberwas next moved vertically upwards to its original position; the cellinsertion member was returned to its original position; and the mobilecell assembly chamber was indexed to the start position where thecompleted cell assembly/battery container module was removed manuallyfrom said chamber.

The entire cycle described above was completed in approximately 35seconds.

Cell assemblies produced as described above were constructed into sealedbatteries without further relative movement of the positive and negativeplates by simultaneously forming integral positive plate straps andposts and negative plate straps and posts by means of a knowncast-on-strap technique utilizing a lead-2% tin-0.08% selenium alloy,filling each cell with approximately 35 grams of 1.28 S.G. sulfuricacid, placing and sealing an inner cover and potting the plate strapsinto said inner cover using a commercially available epoxy cement,inserting a flexible closed-cell polymeric vent cap relative to the ventoutlet in said inner cover, and sealing an outer cover to the cellcontainer using the aforesaid epoxy cement.

Batteries so produced were charged at a constant voltage of 2.40 voltsfor approximately eleven hours, discharged at 5 amperes to a cut-offvoltage of 1.50 volts, and then cycle tested at a 5-ampere dischargerate using a regime of two 15-minute cycles, two 12-minute cycles, two8-minute cycles, repeat. FIG. 11 compares typical discharge curves for abattery produced automatically in accordance with the method of thisinvention and an essentially identical battery for which all steps inthe cell assembly operation were performed manually. These data indicatethat the capacity and performance of the cell assembled automaticallywas essentially identical on the first and ninety-seventh cycles to thecapacity and performance of the cell that was assembled manually. Aswill be obvious to those skilled in the art, the performance of thebattery in which the cell was assembled in accordance with the method ofthis invention is typical of that expected from a lead-acid battery ofthis type.

A preferred approach of establishing the assembly sequentially when theindividual elements are cut from the continuous length and subsequentintroduction of the cell assembly into the battery cell container hasbeen disclosed, but it will be appreciated that the invention is not solimited. For example, the apparatus may be employed to create the cellassembly by sequential introduction of precut and stacked elements.

While for simplicity of illustration, a specific sequence of cutting theseparator stock and plate stock has been illustrated, it will beappreciated by those skilled in the art that other sequences of cuttingmay be employed so long as a functional arrangement of the assembledplates and separators is achieved.

While for simplicity of disclosure, a system having a singlereciprocating assembly chamber has been shown, the invention is not solimited. For example, a plurality of assembly chambers moving in thesame linear path and indexed from component station to component stationmay be employed. Also, a rotary version having a plurality of ofassembly chambers moving in a curved or circular path may be employed.

The battery cell container may be indexed to and move with the assemblychamber, if desired, or may be stationary and be aligned where anassembly is to be inserted.

While certain relationships between the number of plates and separatorshas been directed, the invention is not so limited. For example, theassembly may employ two end separators, one end separator or no endseparators. The end separator may be of the same thickness or differentthicknesses from the intermediate separators. The number of positiveplates may be equal to the number of negative plates or may be one moreor one less than each number.

While certain forms of cutting means for severing material from acontinuous length have been shown, it will be appreciated that a widevariety of cutting means, including but not limited to, shearing andpunching may be employed.

While reference has been made herein to use of electrochemically formedbattery plate stock, it may be appreciated that the invention is alsouseable with as-cured plate stock.

Whereas, particular embodiments of the invention have been describedherein, for purposes of illustration, it will be evident to thoseskilled in the art that numerous variations of the details may be madewithout departing from the invention as set forth in the appendedclaims.

We claim:
 1. Apparatus for making a lead-acid battery comprising,meansfor supplying a continuous length of positive plate stock, means forsupplying a continuous length of separate stock, means for supplying acontinuous length of negative plate stock, means for severing individualseparators and plates from said means for providing continuous lengthsthereof, assembly means for sequentially receiving individual separatorsand plates and establishing an assembly thereof, and means for insertingthe assembly of said separator and plates to a battery cell container.2. The apparatus of claim 1 including,means for providing an endseparator from a continuous length of separator stock, said means forsevering including means for severing said end separator, and saidassembly means having means for adding at least one said end separatorto said assembly.
 3. The apparatus of claim 1 including,said severingmeans including cutting means associated with each said means forproviding continuous lengths.
 4. The apparatus of claim 1, includingsaidassembly means being relatively moveable with respect to said severingmeans, whereby after severing each said separator or plate may betransported to said assembly means directly without intermediatestorage.
 5. The apparatus of claim 4 including,means for transportingsaid assembly means in a path of generally linear movement with respectto stationary said severing means.
 6. The apparatus of claim 5including,said battery cell container means being disposed adjacent tosaid assembly means.
 7. The apparatus of claim 6 including,said assemblymeans having a plurality of alignment means for securing said plates andseparators in desired relative positions.
 8. The apparatus of claim 7including,said alignment means including a plurality of generally spacedupwardly projecting retractable alignment pins.